I always butcher asap. Hanging them for awhile doesn't really do anything IMO other than allow it to be exposed to air born contaminants or insects. The thought of something laying eggs in my deer is enough to give me the willies! [:'(]

However, I always let it "age"in the refrigerator for a few days after taking it from the freezer. You can let it sit in there quite awhile if need be. I've gone over a week on a couple of occasions with no issues. I set the piece on a plate with some paper towels. Once the towel has soaked up a good amount of blood, the meat is usually ready to go.